The design and rationale of an interdisciplinary, non-prescriptive, and Health at Every Size®-based clinical trial: The "Health and Wellness in Obesity" study.

This manuscript describes the design and rationale of a clinical trial that aims to investigate the multiple physiological, attitudinal, nutritional, and behavioral effects of a new interdisciplinary intervention based on the Health at Every Size® (HAES®) approach in obese women.This will be a prospective, 7-month, randomized (2:1), mixed-method clinical trial. Obese women will be recruited and randomly allocated into two groups. The intervention group (I-HAES®; proposed n = 40) will undertake a novel HAES®-based intervention. Participants will take part in an exercise program, nutrition counseling sessions, and philosophical workshops, all aligned with the principles of the HAES® approach. The control group (CTRL; proposed n = 20) will participate in a program using a traditional HAES®-based group format, characterized by bimonthly lectures about the same topics offered to the experimental group, encouraging the adoption of a healthy lifestyle. The following multiple quantitative outcomes will be assessed pre and post intervention: health-related quality of life, cardiovascular risk factors, anthropometric assessments, physical activity level, physical capacity and function, and psychological and behavioral assessments. Qualitative analysis will be used to evaluate the experiences of the participants throughout the intervention, as assessed by focus groups and semi-structured interviews.The interdisciplinary research team leading this study has varied and complementary expertise. The knowledge arising from this study will help to guide new interdisciplinary interventions with the potential to holistically improve the health of obese individuals. This trial is registered at Clinicaltrials.gov (NCT02102061).